1. Field of the Invention
The present invention relates to a solid-state image pickup device, and particularly relates to an element isolation structure of a solid-state image pickup device.
2. Description of the Related Art
Japanese Patent Laid-Open No. 2009-016810 discloses an element isolation structure between a photoelectric conversion portion and a pixel transistor (active element). Specifically, the element isolation structure having the following characteristics is disclosed. First, an element isolation region is formed in a semiconductor region having a conductive type opposite to that of a source region and a drain region of a pixel transistor. Secondly, an insulation film disposed in a region from a channel region of the pixel transistor to the element isolation region is formed in a flat state having no level differences. According to Japanese Patent Laid-Open No. 2009-016810, the area occupied by the pixel transistor can be reduced by such an element isolation structure.